'accession' originates from Latin, specifically the word 'accessio,' where 'ad-' meant 'toward' and 'cedere' meant 'to go.'

'accessio' transformed into the Old French word 'accession,' and eventually became the modern English word 'accession' through Middle English.

Initially, it meant 'an approach or addition,' but over time it evolved into its current meanings of 'attainment of a position' and 'increase by addition.'